Lee sizing dies use a 1/4" or 3/8" National Tapered Pipe Thread for the collet that holds the primer punching mandrel and I need to make a new collet for my .30-06 sizing die. Pipe threads have a 3/4" per foot included-angle taper and I'm trying to figure out a way to cut that tapered thread on my lathe without having to offset the tailstock and machine it between centers. Mounting something that short between centers is a bit difficult to begin with plus I am very reluctant to disturb my tailstock because I just managed to get it adjusted so my lathe can make a 40" cut without any taper in that length, which took about an hour plus required making trial cuts on a 40" length of 1.5" steel bar stock to get it adjusted, and a 40" piece of 1.5" steel bar stock isn't exactly cheap.
Besides machining between centers, a taper bar is the other obvious way, but unfortunately my lathe isn't built with taper bar mounts on the bed or cross feed. It appears that I'm up a creek without a paddle unless there is some obscure way of cutting tapers on short lengths of bar stock on a lathe like mine, although in the past I have faked it a few times by hand-cranking the crossfeed to approximate a taper that was not too critical.
All suggestions welcome, I'll try anything once! Well, almost anything.
rl597